/* This program is free software; you can redistribute it and/or modify
 * it under the terms of the GNU General Public License as published by
 * the Free Software Foundation; either version 2, or (at your option)
 * any later version.
 *
 * This program is distributed in the hope that it will be useful,
 * but WITHOUT ANY WARRANTY; without even the implied warranty of
 * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
 * GNU General Public License for more details.
 *
 * You should have received a copy of the GNU General Public License
 * along with this program; if not, write to the Free Software
 * Foundation, Inc., 59 Temple Place - Suite 330, Boston, MA
 * 02111-1307, USA.
 *
 * http://www.gnu.org/copyleft/gpl.html
 */
package com.it.br.gameserver.util;

import java.util.Arrays;
import java.util.Collection;
import java.util.Collections;
import java.util.List;
import java.util.Map;

import javolution.util.FastList;

/**
 * Descending Integer Sort Algorithm - Fast ordering system. - Can easily be ported elsewhere. - Can handle any number
 * of values, from a list or even from a map. - Handles duplicate values.
 * 
 * @author Tempy
 */
public class MultiSort
{
	public static final int SORT_ASCENDING = 0;
	public static final int SORT_DESCENDING = 1;

	private List<?> _keyList;
	private List<Integer> _valueList;

	private boolean _isSortDescending;
	private boolean _isSorted;

	public MultiSort(int[] valueList)
	{
		_valueList = getIntList(valueList);
	}

	public MultiSort(Collection<Integer> valueList)
	{
		_valueList = getIntList(valueList);
	}

	public MultiSort(Object[] keyList, int[] valueList)
	{
		_keyList = getList(keyList);
		_valueList = getIntList(valueList);
	}

	public MultiSort(Map<?, Integer> valueMap)
	{
		_keyList = getList(valueMap.keySet());
		_valueList = getIntList(valueMap.values());
	}

	private final List<Integer> getIntList(Collection<Integer> valueList)
	{
		return Arrays.asList(valueList.toArray(new Integer[valueList.size()]));
	}

	private final List<Integer> getIntList(int[] valueList)
	{
		Integer[] tempIntList = new Integer[valueList.length];

		for(int i = 0; i < valueList.length; i++)
		{
			tempIntList[i] = new Integer(valueList[i]);
		}

		return Arrays.asList(tempIntList);
	}

	private final List<?> getList(Collection<?> valueList)
	{
		return getList(valueList.toArray(new Object[valueList.size()]));
	}

	private final List<Object> getList(Object[] valueList)
	{
		return Arrays.asList(valueList);
	}

	public final int getCount()
	{
		return getValues().size();
	}

	public final int getHarmonicMean()
	{
		if(getValues().isEmpty())
			return -1;

		int totalValue = 0;

		for(int currValue : getValues())
		{
			totalValue += 1 / currValue;
		}

		return getCount() / totalValue;
	}

	public final List<?> getKeys()
	{
		if(_keyList == null)
			return new FastList<Object>();

		return _keyList;
	}

	public final int getFrequency(int checkValue)
	{
		return Collections.frequency(getValues(), checkValue);
	}

	public final int getMaxValue()
	{
		return Collections.max(getValues());
	}

	public final int getMinValue()
	{
		return Collections.min(getValues());
	}

	public final int getMean()
	{
		if(getValues().isEmpty())
			return -1;

		return getTotalValue() / getCount();
	}

	public final double getStandardDeviation()
	{
		if(getValues().isEmpty())
			return -1;

		List<Double> tempValList = new FastList<Double>();

		int meanValue = getMean();
		int numValues = getCount();

		for(int value : getValues())
		{
			double adjValue = Math.pow(value - meanValue, 2);
			tempValList.add(adjValue);
		}

		double totalValue = 0;

		for(double storedVal : tempValList)
		{
			totalValue += storedVal;
		}

		return Math.sqrt(totalValue / (numValues - 1));
	}

	public final int getTotalValue()
	{
		if(getValues().isEmpty())
			return 0;

		int totalValue = 0;

		for(int currValue : getValues())
		{
			totalValue += currValue;
		}

		return totalValue;
	}

	public final List<Integer> getValues()
	{
		if(_valueList == null)
			return new FastList<Integer>();

		return _valueList;
	}

	public final boolean isSortDescending()
	{
		return _isSortDescending;
	}

	public final boolean isSorted()
	{
		return _isSorted;
	}

	public final void setSortDescending(boolean isDescending)
	{
		_isSortDescending = isDescending;
	}

	public boolean sort()
	{
		try
		{
			List<Object> newKeyList = new FastList<Object>();
			List<Integer> newValueList = new FastList<Integer>();

			// Sort the list of values in ascending numerical order.
			Collections.sort(getValues());

			int lastValue = 0;

			if(!isSortDescending())
			{
				// If there are no keys, just return the ascendingly sorted values.
				if(getKeys().isEmpty())
					return true;

				// Iterate through the list of ordered numerical values.
				for(int i = getValues().size() - 1; i > -1; i--)
				{
					int currValue = getValues().get(i);

					// If the current value is equal to the last value, we have at least one
					// duplicate that has been outputted already, so continue.
					if(currValue == lastValue)
					{
						continue;
					}

					// Set the last value to the current value, to prevent duplication.
					lastValue = currValue;

					// Iterate through each key and match it to its stored integer value,
					// then output both sets of data in the correct descending numerical order.
					for(int j = 0; j < getKeys().size(); j++)
					{
						Object currKey = getKeys().get(j);

						if(getValues().get(j) == currValue)
						{
							newKeyList.add(currKey);
							newValueList.add(currValue);
						}
					}
				}
			}
			else
			{
				// If there are no keys, just sort the value list in reverse order.
				if(getKeys().isEmpty())
				{
					Collections.reverse(getValues());
					return true;
				}

				// Do the exact same as above, but in descending order.
				for(int i = 0; i < getValues().size(); i++)
				{
					int currValue = getValues().get(i);

					if(currValue == lastValue)
					{
						continue;
					}

					lastValue = currValue;

					for(int j = 0; j < getKeys().size(); j++)
					{
						Object currKey = getKeys().get(j);

						if(getValues().get(j) == currValue)
						{
							newKeyList.add(currKey);
							newValueList.add(currValue);
						}
					}
				}
			}

			_keyList = newKeyList;
			_valueList = newValueList;
			_isSorted = true;
			return true;
		}
		catch(Exception e)
		{
			return false;
		}
	}
}
